The invention relates to a device for fastening at least one plate inside an electrolyte bath and for feeding current thereto, which device comprises at least one electrically-insulated batten wherein at least one electric conductor is imbedded, which conductor can be connected to a current source, and means to insure the electric contact between the conductor and the plate.
Such devices are notably used for manufacturing so-called printed circuits. A plate from electrically-insulating material having already some metal plating, is arranged thereby inside an electrolyte bath and by feeding current to said plating, metal is caused to precipitate over the complete plating or according to a determined pattern by covering partly said plating.
In known devices of this kind, one or a plurality of such battens with an imbedded conductor are so fastened substantially vertically to a cathode bus bar that said battens are immersed into the electrolyte bath. Inside the bath proper, to said batten are fastened clamps which are also electrically insulated by means of a synthetic material coating, but not in those locations where said clamps are to contact the plate. The conducting core of said clamps is connected to the batten conductor. The clamps proper are tightened down on a plate by means of screws. Due to said screws and wear, the clamp insulation is quite rapidly damaged. As soon as the insulation is removed, there also occurs a plating of the clamps proper which thus means a loss of material.
When removing the metal plating from the clamps, there is again a danger that the clamps will be further damaged, whereby during the following use still more clamp plating will occur.
With other devices, the clamps are formed by springs which engage the batten conductor by means of a bolt. The above-described drawbacks are also to be found in these latter devices.
In still further devices, the clamps have no screw but the device comprises two battens which are immersed vertically in the bath, and which are provided on the sides thereof facing one another with contact springs with a groove, the plate being clamped with the upstanding edges thereof between said springs. Not only there is still obtained some precipitating on the springs but also due to the contact springs engaging two facing edges of the plate, with other plate sizes said springs and thus also the battens with the conductor have to be moved.
Now to solve the problems of metal plating on the clamps, it has already been proposed not to immerse the clamps in the electrolyte bath but to retain same above said electrolyte bath. With this solution, there is thus no problem with metal plating of the clamps, but part of the plates has to project above the electrolyte bath and thus is not used purposefully.